I've been using a Rotatrim "Professional M" series cutter 24" version for 10+ years. My cutter was manufactured in 2001, and it works flawlessly. To cut larger prints I ordered a 36" version, assuming the design would be identical to the one I have. There is a variation - unlike my 24" cutter the plastic strip, under which you slide the print, is not flush with the cutting edge; it is about an 1/8" offset from the edge. As a result you cannot visually determine where the blade will trim the print. I don't see the logic of this design and Rotatrim's distributor/customer-service in the US - Manfrotto Distribution don't bother to return customer enquires. Anyone on this forum care to shed light on this issue?

The company from which I bought the cutter - CalumetPhotgraphic in Cambridge, MA said to me that that's how the design is, and that's how all Rotatrim cutters are, and took the cutter back for a full refund.

Manfrotto UK suggested that I use the scale to determine where the cut should be made rather than making a visual determination. This is not practical as the scale on the cutter is rather short.

I have a 42inch model that I purchased maybe 8 years ago and all I can say is that mine is similar. The plastic strip is also uneven. Furthermore, the guide is not square to the cutting edge either.

I have the 24 inch model and mine isn't square either. I did try to fix it once, read instructions somehwhere on removing the screws on the edge on the left, but just couldn't get it quite right.

Back to the original issues, I had no idea that plastic strip would be flush with the edge for the model before. I imagine some people may have been cutting into the plastic if it hung over the edge. For precise work, I use the metal edge on both sides as my visual guide, meaning I see how much of the print is hanging past that metal edge and hence that piece will be chopped off once the cut is made.

I am happy to say that my cuts are still perfect after many years of use, but improvements could be made!

You can contact him but you will probably find that's how they are - mine is too. It is a slight irritant but I have been using it for many thousands of cuts over quite a few years and it is really excellent. I use the metal base edge as my guide and can judge it quite well.

My 24" Rotatrim is the same, and also not quite perfectly square. I haven't messed with it as it's been good enough.

<rant>Man-0-Man! You know how hard it is to get a square SQUARE these day? I needed to tune my 60" mat cutter and went through 4 different stores looking for a good carpenter's square that was true before I found one 'good enough'. You can buy a woodpecker's, but they are really expensive!</rant>

Having recently purchased a 24" Rotratrim model I can say with certainty that this plastic hold-down guide is a PITA!!!. As others have noted, it's just slightly askew of the true cut line which makes it hard to actually see where the print is really going to be cut. On my new unit the screws securing this plastic guide have no adjusting tolerance, so the problem cannot be corrected. Moreover, I truly dislike having to slide delicate inkjet media under that plastic guide since it flexes open very little. I tried simply removing it (which admittedly exposes one's fingers to the blade, but then the cutter doesn't cut reliably, so this hold-down clamp is indeed necessary and a part of the functional design. That said, when I get a little free time I will make some real modifications to improve what is unquestionably the worst problem with the current design.

On a shorter cutter I removed a similar loose strip and made a triangular one that is fixed outside the cutting area to the cutter, on the short side of the triangle. The edge is spot on the cutting edge. I have to lift that triangle to slide the print underneath. Could add a picture tomorrow. On the board cutter, 5 feet long, I have a thin transparent PET strip adhered to the pressure bar and then cut so the edge is precisely represented. From time to time I have to replace that one when the edge is weared off. Modern motorised cutters have a laser line projected.

My quick workaround was to tape a piece of thick paper to the underside of the plastic strip to use as a guide (I used a strip of photo paper and double-sided tape.)

The paper strip should extend beyond the cutting edge when taping it to the plastic strip, and then cut it to size using the cutter. This way the paper strip and the cutting edge are perfectly aligned.

Next, I cut little V shaped notches every few inches on the cutting edge of the paper guide to help with viewing the piece while positioning. I also bent the edge of the guide paper opposite the cutting edge upward to help slide the work underneath.

<rant>Man-0-Man! You know how hard it is to get a square SQUARE these day? I needed to tune my 60" mat cutter and went through 4 different stores looking for a good carpenter's square that was true before I found one 'good enough'. You can buy a woodpecker's, but they are really expensive!</rant>

Get the largest sheet the cutter can handle. Cut one side, mark it, then cut the edges with the sheet rotated clockwise (righthand cutter, like my board cutter, not the Dahle) and check the last 90 degr corner created, it is a 3x cumulation of the 90 degr register bar fault, so lay that corner against the bar again. Easy to check what correction you have to make but only 1/3 of what you see. Repeat that method. Measure the diagonals of the sheet as a last step. No way you can get that precision with a square.

I got a response from the product manager for Rotatrim. Thank you Jon for suggesting I contact him, he was indeed helpful. Here's the response.

Thank you for your email with regard to your Rotatrim Professional trimmer. While I am extremely pleased that your existing Professional M24 trimmer has given you 10+ years of excellent service and I am sure it will continue to do so, I am disappointed that you have felt that there is an issue with the Professional M36 that you purchased.

You are correct that the clamp strip is set slightly back from the edge of the flat (counter) blade, this is by design and is to ensure that the clamp strip is not moved into the path of the cutting wheel which could subsequently cause damage when a cut is made. The clampstrip was never intended to be used as a guide to trimming, its purpose is to both clamp the material in place during the cut and also provides a path for the cutting wheel's rubber roller to run along allowing the turning motion needed to make the cut.

The gap between the edge of the flat blade and the clampstrip should be around 1/16" (1.6mm) and not 1/8" (3.2mm) as seems to be the case with the M36 that you purchased. It is possible that the clampstrip on the machine that you purchased had bowed and as such was sitting further from the edge of the flat blade towards the middle of the machine. I know that you have now returned the machine but can you recall if the distance between the edge of the flat blade and the clampstrip was consistent across the machine or was larger greater the middle of the machine?

As a result of your email I had a look at the "Luminous Landscapes" forum, on which there were some comments on the rule going out of square, this can happen over time and with prolonged use, however the design of the machine makes this very easy to rectify. Just in case you should face this issue with your existing M24 trimmer, I have attached a set of instructions on squaring the rule.

I am also extremely surprised that you did not receive a response from our distributor Manfrotto as they usually offer excellent customer service and did actually contact one of my colleagues following your email to them, to which he responded in line with the content of this email. I will contact Manfrotto to enquire as to why this enquiry was not followed up to their usual high standards.

It is possible that the DigiTech+ or the Technical series of machines may resolve the issue, as the clamp strip is of a completely different design. However, there must still be a gap between the edge of the flat blade and the edge of the clampstrip for the same reasons outlined above.

To summarise: -There does have to be a gap between the edge of the flat blade and the clampstrip, such that the clampstrip is not damaged during the cutting process.The clampstrip was not designed as a cutting guide, however we do understand that on your older machine as it was closer to the edge, you were able to use it as a such.It would seem that the gap on the M36 you purchased may have been larger than we would normally expect, maybe due to the clampstrip bowing.It is likely that another M36 machine would not have such a large gap between the clampstrip and edge of the flat blade.

I trust that this addresses your concerns with the M36 and the differences that you saw between that machine and the M24 that you have had for sometime. If there is any way in which I can further assist you then please feel free to contact me, at any time.

Get the largest sheet the cutter can handle. Cut one side, mark it, then cut the edges with the sheet rotated clockwise (righthand cutter, like my board cutter, not the Dahle) and check the last 90 degr corner created, it is a 3x cumulation of the 90 degr register bar fault, so lay that corner against the bar again. Easy to check what correction you have to make but only 1/3 of what you see. Repeat that method. Measure the diagonals of the sheet as a last step. No way you can get that precision with a square.

Ernst

Good tip, thanks. Having had to deal with the "unsquare square" problem it is most welcome.

Rxchaos: could you post the manger's proceedings for 'squaring' the cutter? Does Dinkla's suggestion supplement and/or differ from Rotatrim's?

I would like to correct the ~1/32 error I encounter when trimming a sheet in half to get 2 equal parts. I use the left ruler select the 1/2 size dimension but get this slight error. If I mark the 1/2 size size cut and align it with the upper metal cutting edge the cut is OK.

I have also placed a strip of Teflon tape underneath the plastic guide in an attempt to minimize micro-scratches on the print's coated surface.

I have been using the M24 (for 18 mos) to size and trim Canvas media with great success, the clean trimming of 'slivers' is remarkable!